The present invention relates generally to projection television sets, and more particularly to optical unit brackets designed for attachment to projection television sets and projection television set enclosures incorporating the brackets.
Projection television sets are a popular alternative to picture tube television sets, as they provide relatively large viewable screens that cannot be efficiently produced using conventional picture tubes. Projection television sets typically include an enclosure with an optical unit, a mirror, and electronic components for receiving and projecting an image onto a screen assembly mounted on the front of the enclosure.
A current, typical projection television set 100 is shown in FIGS. 1A-1C. Turning to FIG. 1A, the components of the projection television set 100 are illustrated. The projection television set 100 has an optical unit 10 that generally includes a set of projection units 20R, 20G, and 20B. Each projection unit projects an image, generally of a single color of light (red, green, or blue), onto the mirror M in the enclosure (not shown), which focuses the image onto an inside surface of the screen S. Each projection unit 20R, 20G, 20B includes a cathode ray tube (CRT) 22R, 22G, 22B, a projection lens assembly 45R, 45G, 45B, and a spacer 28R, 28G, 28B interposed between each respective CRT and projection lens assembly. The projection units 20R, 20G, 20B are mounted to a bracket 50. The bracket 50 is attached to a pair of enclosure mounting brackets 55a and 55b that hold the bracket 50 in place within the enclosure (not shown). Attachment elements 57a, 57b, which may be, e.g., screws or some other anchoring elements, secure the bracket 50 to the mounting brackets 55a, 55b. 
FIG. 1B shows a side cut-away view of a current projection television set 100 having an enclosure 105 to contain the components previously described. The enclosure 105 is typically divided by an internal wall 112 into two compartments, an upper compartment 114 and a lower compartment 116. The internal wall 112 tightly seals the upper compartment 114 from the lower compartment 116 to protect the inside of the upper compartment 114 from dust and other foreign materials. The optical unit 10 is typically mounted in the lower compartment 116, while the mirror M and screen S are mounted in the upper compartment 112. Furthermore, the optical unit 10 typically extends from the lower compartment 116 into the upper compartment through the internal wall 112. The lower compartment 116 generally includes one or more sets of ventilation holes 118 to exhaust heat radiating from the optical unit 10 and any other components, such as, e.g., printed wiring boards (not shown) that may be located in the lower compartment 116.
To properly function, the projection units 20R, 20G, 20B of the optical unit 10 must be aimed at the mirror M along a predetermined, optimal angle. Consequently, mounting bracket 55 is configured to hold the bracket 50 in place within the enclosure 105 at a predetermined angle. The enclosure mounting brackets 55a and 55b hold the bracket 50 at an angular orientation substantially equal to the optimal angle of operation of the projection units 20R, 20G, 20B, thereby enabling the proper functioning of the projection units 20R, 20G, 20B. FIG. 1C is a top view of the enclosure 105 taken along line 1C in FIG. 1B. FIG. 1C illustrates the attachment of the mounting brackets 55a, 55b to the enclosure 105, and the attachment of the bracket 50 to the mounting brackets 55a, 55b. Attachment elements 59a, 59b are used to attach the mounting brackets 55a, 55b to the enclosure 105, and attachment elements 57a, 57b are used to attach the bracket 50 to the mounting brackets 55a, 55b. 
The existing techniques for mounting the optical units of projection television sets have their disadvantages. The requirement for enclosure mounting brackets to secure a bracket to an enclosure results in an increase in the complexity of producing projection television sets. For example, construction, assembly, and attachment of the optic units to the bracket and further to the enclosure mounting brackets tends to be cumbersome and, thus, labor intensive. In addition, as previously discussed, the enclosure mounting brackets must be set at the proper angle in each individual projection television set in order to ensure that the optical units are aimed in the proper direction. The need to ensure that the enclosure mounting brackets are attached to each individual enclosure at the proper angle introduces variables, such as tolerance stacking, into the production of each individual set. As a result, the possibility of a defectively produced projection television set due to an improperly attached enclosure mounting bracket is increased. Therefore, it would be desirable to provide for a more efficient and reliable means for properly mounting the optical units to the enclosures, and apparatuses for accomplishing those means.
The present invention is directed to an improved projection television set enclosure that includes side panels and an optical unit bracket attached to the side panels without the need for the enclosure mounting brackets currently utilized by those skilled in the art. In one embodiment, a projection television set is provided that comprises an enclosure, a screen, a mirror, and an optical unit that includes a plurality of projection assemblies and an optical unit bracket. The enclosure includes an upper compartment to house the screen and mirror. The enclosure also includes a lower compartment, attached to the upper compartment, that has a front panel, a rear panel, and a plurality of side panels. At least two of the side panels of the lower compartment each have an angled top surface to which the optical unit bracket is attached. The optical unit bracket may be attached to the side panels using attachment elements, such as, e.g., screws and the like. Preferably, the angled top surface of each side panel is oriented to point the optical unit at the mirror along a predetermined angle when the optical unit bracket is affixed to the angled top surface.
The optical unit bracket of this embodiment of the present invention includes a first end and a second end, each end having a horizontal extension and a vertical wall adjacent the horizontal extension. The horizontal extension is placed on top of the angled top surface of a side panel and the vertical wall is placed adjacent the side wall. Preferably, the horizontal extension and the vertical wall are located at an approximately ninety degree angle relative to each other. The vertical wall may also include a plurality of openings through which attachment elements are inserted to affix the bracket to the side wall.
In another embodiment, a projection television set is provided that includes a screen, a mirror, an enclosure, and an optical unit comprising a plurality of projection assemblies and an optical unit bracket. The enclosure includes an upper compartment to house the mirror and screen, and a lower compartment attached to the upper compartment. The lower compartment includes a front panel, a rear panel, and a plurality of side panels. At least two of the side panels of the lower compartment have angled openings through which the optical unit bracket is inserted and secured. The openings are angled to aim the optical unit towards the mirror along a predetermined angle. Preferably, the optical unit bracket has a first end and a second end, with each end being substantially the same size and shape as an angled opening on a side panel such that, once inserted into the openings, the optical unit bracket is fixed to the side panels. Additionally, an adhesive may be placed around the circumference of the first and second ends of the optical unit bracket to further ensure that the optical unit bracket is secured to the side panels.
In another embodiment, rather than having either angled openings or angled top surfaces, the side panels of the lower compartment of an enclosure of the present invention have a bracket mounting member attached thereto. The bracket mounting member preferably includes an elongate body with a top surface, a bottom surface, and first and second ends. The bracket mounting member also preferably includes a notch extending between the first and second ends and along the top surface of its elongate body. The notch of the bracket mounting member receives and engages a detent that is located on the underside of one embodiment of the optical unit bracket. In this embodiment, the optical unit bracket includes detents on its first and second ends, on the underside of the bracket, extending along the width of the bracket.
Other objects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.